CP-424,391 is a potent, non-peptidyl growth hormone (GH) secretagogue that significantly increases both GH and insulin-like growth factor-I (IGF-I) levels in animals and healthy humans. As GH is anabolic, several studies with exogenous GH in patients with catabolic illnesses have shown encouraging (but not definitive) results. The present study will examine, under carefully controlled conditions, the use of CP-424,391 in mildly obese healthy men and women using a model of catabolic illness: caloric deprevation.